Out of the box, FOViewer doesn't know about projections outside of North America (sorry about that).

For the rest of the world, to see you data mapped correctly, you will have to manually enter the EPSG code.  This is done by right-clicking the left most map toolbar button (preferences).

Southern codes are "327" + <UTM Zone Number>.   So, New Zealand, for instance (which is zone 60), would be "32760".

Northern codes are "326" + <UTM Zone Number>.   

These are WGS84 datums.